The present invention relates to an inflation valve, especially to an inflation valve that allows air flowing into air bags such as life jackets or life rafts for inflation.
Generally an inflation valve is a one-way valve that includes a valve body and a valve member. The valve body is disposed with a channel and a valve seat while the valve member consists of a rod whose front end is connected with a valve head. The valve member is set in the channel and is passing the valve seat axially. The valve member moves forwards and backwards repeatedly so as to open or close the inflation valve.
Refer to U.S. Pat. No. 3,396,743, a checked valve for air intake and exhaust is revealed. The check valve includes a first and a second annular valve seats moveable relative to each other so that the production cost is high and the maintenance is poor.
Refer to U.S. Pat. No. 4,176,681 and U.S. Pat. No. 4,305,425, a oral inflation valve is disclosed. The valve has a valve body and a movable valve element therein. The valve element has a body which carries an annular sealing means. This device also has shortcomings of high production cost and poor maintenance.
Refer to U.S. Pat. No. 4,129,145, a check valve assembly having a hollow valve body is disclosed. A seal member (deformable resilient O-ring) circumscribes a poppet element at the neck of the poppet. The O-ring is pressed against a seating surface by fluid flowing through the valve body to close the valve. While once the pressure in the valve assembly is larger, the seal member is easily falling off due to the pressure so as to cause leakage of the fluid.
Refer to U.S. Pat. No. 4,836,235, a tire valve revealed includes an elastic valve body having a through passageway formed therein, with a constriction formed at an intermediate portion of the through passageway. A valve pin is provided with a gasket and is mounted to slide directly within the constriction at the intermediate portion of the through passageway. When the pressure in the valve becomes larger, the gas tightness is reduced once an enlarged head on the valve pin leans against inner wall of the valve body. Moreover, at least one of the valve pin and the valve body is made from elastic material and this is difficult to manufacture in practice.
Refer to U.S. Pat. No. 5,135,025, an articulated oral inflation valve is revealed. A valve stem of the valve has a trailing end in the form of a spherical ball and a socket carried by a valve head rotatably receives the ball. Yet the assembling of multiple components increases the production cost and the assembling is time consuming. Moreover, the defective rate of the products is quite high and the maintenance of products is difficult.
Refer to U.S. Pat. No. 5,297,576, an oral inflation and relief tube for connection to an inflatable article is disclosed. The structure is similar to the U.S. Pat. No. 4,305,425 so that this device also has disadvantages of high production cost and poor/difficult maintenance.
Thus the above prior arts are with several shortcomings such as complicated structure, high production cost, difficulties in assembling, poor or difficult maintenance, and insufficient strength of the whole structure. Moreover, when the pressure in the valve is larger, sealing members are easy to fall off or poor gas tightness is occurring. Thus there is a need to provide a new design of the inflation valve that makes the assembling become more convenient, improves the strength of the whole structure as well as the gas tightness, and further reduces the production cost.